i don't really have any suggestions on what unit to use. but i have a few comments since i've used a few units before, mainly civilian. for some reason, whenever i go hiking, i tend to go places where the cell phone doesn't work, radio signals are weak, and there is too much canopy cover to get a decent satellite signal. so if you're looking to get one because you don't want to learn how to use a map and compass it's a bad idea. as a backup though, they're great, makes life a whole lot easier when they're working.